Grate bar



1933- J. s. THOMPSON ,93

GRATE BAR Filed Feb. 25, 1930 ATTORNEYS Patented Oct. 17, 1933 UNITED STATES PATENT OF FlCE GRATE BAR poration of Maine Application February 25, 1930. Serial No. 431,284

i 3 Claims.

This invention relates to a rocking grate bar of the type now widely used in locomotives, boiler furnaces and the like. More specifically, the invention is concerned with a grate bar made up 5 of a carrier member and a plurality of fuelsupporting elements mounted thereon, these elee ments being readily removable from the member and replaceable thereon and'being provided with locking means brought into operation on rocking of the member, to hold the elements and member together and to prevent accidental dislodgment of the elements.

In the co-pending application of Buckley, Serial No. 338,352, filed February 8, 1929 now Patent No. 1,884,557, October 25, 1932, is disclosed and claimed a grate bar which comes within the terms of the above general description. The Buckley bar includes a carrier memher in the form of a web having an upstanding flange, and the fuel-supporting elements have openings therein so that they may be slipped laterally over the carrier member to rest on the flange. These elements have spaced lugs one on each side of the opening and these lugs 5 are so placed that whenthe carrier member is rocked and the elements swing relatively there to about the top of the flangeas an axis, one or the other of the lugs of each element engages beneath the edge of the web and serves to. lock the element to the member to prevent their complete separation.

When the Buckley bar is installed in a 1000- motive, the constant jarring of the structure causes the elements to rock on the flange of the carrier member due to the slight freedom of movement that the elements have relative to the member and the bar consequently has a self-cleaning action, but the elements areliable to assume slightly canted positions in which they do not present a flat fuel-supporting surface throughout the grate. This is objectionable to some extent particularly if it shouldhappen that the elements on two adjacent members are inclined in opposite directions.

The present invention is accordingly directed to an improvement on the Buckley bar which overcomes the objections above pointed out. In the new bar, a carrier member is employed, and fuel-supporting elements are detachably mounted thereon. The member is provided with spaced supporting surfaces on which the elements rest, the elements normally having contact with these surfaces only. The member and each element have co-operating parts which are efiective upon rocking of the member to lock the member and element together and these parts are so positioned'as not to interfere with removal and replacement of the elements in a direction laterally of the member arises.

When the new bar is rocked to shake the grate, the carrier member first moves relatively to the elements, which tend to remain at rest by reason of the Weightof the fuel thereon. In this initial movement of the carrier'member, it' swings about the end of one supporting surface as a fulcrum, and the relative movement continues until certain parts on the member and elements bend and cause the elements to move with the member as the rocking continues. At this stage of the movement, the lockingpa'rts of the member and elements become effective to secure the elements to the member. When the member is rocked in the opposite direction, the reverse sequenceof operations takes place so that when the member has returned to its original position, the elements again lie with their fuel-supporting surfaces horizontal.

For a better understanding of the invention, reference may be had to the accompanying drawing, in which Fig. 1 is a sectional view through the grate bar in ordinary working position;

Fig. 2 is a similar View showing the parts at one stage in the rocking movement; and

Fig. 3 is" a similar view showing the parts at the end of the rocking movement.

Referring now to the drawing, the new bar is illustrated as comprising a carrier member 10 which may take diiferent forms but is here illustrated as including a web 11 which is provided at its top with spaced supporting surfaces 12. These surfaces are inclined upwardly toward the longitudinal axis of the member and between them the member is providedfwith an upstanding guide and stop extension 13. Below the web, the latter is provided with a strengthening rib 14 and at one point it has the usual downwardly extending arm 15. At its ends, the carrier member has upwardly projecting extenwhen occasion new sions 16 provided with trunnions 17 of the usual which extend upwardly and merge with up wardly extending projections 20, the tops of which are sub-divided by channels 21 to provide a multiplicity of small fuel-supporting areas.

The element has an opening in the plate generally similar in shape to the cross-section of the carrier member and this opening is of such size that the element may be mounted on the carrier member by a movement at right angles to the longitudinal axis of the latter. Ordinarily in assembling the bar, the carrier member is placed in position in the grate frame and the elements lowered in place to rest on the member. Each element is provided with a pair of surfaces 22 which restin contact with the inclined surfaces 12 at the top of the member and between the surfaces 22, the plate is cut away to form a recess 23 to receive the flange 13 freely and without contacting therewith. At the lower end of the opening are formed projecting lugs 24, the distance between the faces of which is slightly greater than the overall width of the flange 11, this arrangement permitting the elements to be lowered verticallyinto position on the member and raised vertically therefrom. Or-

dinarily the elements occupy the position illustrated in Fig. 1.

As the carrier member. is rocked to dump the grate, it first assumes the inclined position illus-- trated in Fig. 2. As there is a clearance between the extension 13 and the walls of the recess 23, the carrier member first rocks relative to the elements, swinging about the point 25 as a fulcrum, until the sides of the extension 13 begin to bind at opposite sides of the recess 23 at the points 26 and 27, respectively. This movement of the carrier member relative to the elements occurs because the elements tend to remain in their ordinary horizontal position by reason of the weight of the fuel carried thereon. As the rocking of the bar continues, the end 28 of the web moves into the recess 29 at one side of each element to occupy the position shown in Fig. 3. Due to the fact that the lug 24a at the side of the recess now lies beneath the end 28 of the web, the element and carrier member are locked together and the elements cannot be dislodged from the carrier.

Upon the return rocking movement, the reverse sequence of operations takes place. The parts first assume the position shown in Fig. 2, then the position shown in Fig. 1 and in this latter position, the locking parts are ineffective so that the fuel-supporting elements can be readily removed from the carrier member by an upward movement. Also the elements lie with their fuel-supporting surfaces horizontal.

The fulcrum action of thecarrier member about one or the other of the upper outer corners of the web together with the clearance between the recesses in the elements and the extension 13 permits the carrier member to be rocked to a slight degree without causing a corresponding movement of the elements. This facilitates the shaking action because the fireman in pulling on the shaker handle is obliged first to move only the several carrier members throughout the entire grate. These parts are started easily and after a movement of slight extent become locked to the fuel-supporting elements, whereupon the initial dumping action commences. Since the fireman does not have toexert force at the start of the shaking operation suflicient to tilt all of the fuel-supportingelements, he can move the handle rapidly and thus give the carrier bars a considerable momentum which assists in effecting dislodgement of the fuel-supporting elements from the horizontal. On a grate in which the fuel-supporting elements are rigid or integral. with the carrier member, shaking is sometimes an arduous operation, since the initial pull on the shaker handle causes all the elements to swing and thus cause a general movement of the fuel bed. That difficulty in shaking, however, is not presented with the new grate bars for the reasons given.

It will be seen that in the new bar there are a plurality of these fuel-supporting elements mounted side by side on the carrier member and a any one of these elements may be removed without disturbing the others. When the carrier member is in its normal upright position, the elements thereon are so disposed that their fuelsupporting surfaces lie substantially in a horizontal plane and since each element rests in contact with the carrier member at two points, the elements do not have any tendency to swing or rock due to vibration. When thegrate bars are rocked, the initial movement of the carrier member relative to the'elements causes thejelements to be locked to the carrier member-and accidental displacement of the elements from the member is prevented regardless of the vio-' lence of the shaking action. When the shaking is completed and the carrier member restored to its normal position, the elements thereon likewise assume their original horizontal positions by reason of the action described, so that throughout the grate,- the fuel is supported on surfaces which lie substantially'in a plane.

Iclaim: I v 1. A grate bar which comprises'a carrier member adapted tobe rocked and having 'a longitudinal web, a fuel-supporting element resting on said member and normally in contact with said web only and at spaced points, saidelement having an opening therein similar in shape to the cross-section of said member and sufliciently large to permit movement of said member rela-' tive to said element upon rocking of the latter, and spaced parts on said element one on each side of said opening, said parts being spaced a distance greater than'the overall width of said web, and adapted to engage beneath said. web in alternation to lock said element and member together upon rocking of said member in opposite directions. 7

2. A grate bar which comprises a carrier memher having upstanding arms at its ends provided with trunnions near the upper ends of said arms,

said member including a web having at its top spaced supporting surfaces, said surfaces departing from a horizontal plane by a slight'upward convergence and of the web on its top between said surfaces, a plurality of fuel-supporting elements mounted on said carrier member, each element having an opening through it similar in contour to the cross-section of said member, said opening being shaped to permit said element to 'rest on said surfaces without normally contacting with said flange and with other parts of said web and said opening having side walls in a portion thereof which lie substantially parallel to the sides of said flange and at a slight distance therefrom; and spaced lugs on said element one on each.

side of said oryening and normally lying beneath the lower surface of said web and spaced there'- a flange extending lengthwise from, said member upon initial rocking thereof on its trunnions swinging about a point on one of said surfaces of each element as a pivot with said flange engaging said side walls of said openings in said elements, and one of said lugs of each I element also contacting with the under surface of said web, whereby said member and elements are locked together for further rocking movement in unison.

3. A grate bar which comprises a carrier member having supporting means at its ends permitting said member to be rocked, said member including a web having at its top spaced supporting surfaces departing from a horizontal plane by a slight upward convergence and a flange extending lengthwise of the web on its top between said surfaces, a plurality of fuelsupporting elements mounted on said carrier member, each element having an opening through it similar in contour to the cross-section of said member, said opening being so shaped as to permit said element to rest on'said surfaces without normally contacting with said flange and with other parts of said web and said open ing having side walls in a portion thereof which lie substantially parallel to the sides of the flange and at a slight distance therefrom, and spaced lugs on said element one on each side of said opening and normally lying beneath the lower surface of said web and spaced therefrom;

said member upon initial rocking thereof swinging about a point on one of said surfaces of each element as a pivot With said flange engaging said side walls of said openings in said elements and one of said lugs of each element also contacting with the under surface of said Web, whereby said member and elements are locked together for further rocking movement in unison.

' JAMES S. THOMPSON. 

